1$Id: BUGS,v 1.2 1999/12/04 00:01:20 wwg Exp $ 2 wavplay-1.4.tar.gz 3 Fri Dec 3 23:26:20 1999 4 Warren W. Gay VE3WWG 5 mailto:ve3wwg@home.com 6 7There are still issues in wavplay regarding certain legal, but unusually 8formatted wav files that it does not handle correctly. 9 10================ 11COMMON PITFALLS: 12================ 13 14Many emails I get are related to the following user errors: 15 16 1. The user never installed the release patches. At this time 17 there are no patches for release 1.4, but if you do 18 experience problems, please check to see if patches 19 have been released by the time you read this. You can 20 also check http://members.home.net/ve3wwg for pointers 21 to software and patches. 22 23 2. If you are installing the X component xltwavplay, which 24 is entirely optional, then make sure that you've first 25 installed X, its libraries and its include files. Second, 26 make sure you have MOTIF or LessTif installed correctly. 27 These are major sources of user problems. 28 29 3. If you are compiling xltwavplay, then make sure you go 30 over the Makefile. There are a number of places where 31 directories and linking options may need to change based 32 upon your X/MOTIF/LessTif installation. 33 34 4. Keep in mind, that if you are using LessTif, that the 35 LessTif effort is still in progress. LessTif is getting 36 pretty cool these days (at least if you like X/MOTIF). 37 However, there may still be issues that are not related 38 to this software. 39 40=============================== 41SOUND GLITCHES AND LIMITATIONS: 42=============================== 43 44The wavplay-1.0 release was compiled without any of the real time 45benefits that can be had under LINUX. At the suggestion of Dirk Pfau at 46pfau@dkrz.de, I have since added a call to sched_setscheduler() to 47incorporate LINUX real time scheduling, provided you configure 48SCHED_PRIORITY in the Makefile (by default this is configured with a 49real time priority of 9). 50 51The sched_setscheduler() call should work quite well in giving the 52wavplay server (only) the necessary system priority to play sound 53samples without gaps or glitches. If a busy system still causes 54playing/recording to glitch then you may want to use a higher valued 55SCHED_PRIORITY value (assuming you have other real time tasks running on 56your system). This real time scheduling, should improve your recordings. 57 58============ 59SETUID ROOT: 60============ 61 62In order to call sched_setscheduler() with a SCHED_PRIORITY of more than 630 (to be useful), you must have root privileges. This is because you are 64gaining improved scheduling privileges this way. Running any program as 65root has its security drawbacks. I have endeavoured to only run as root 66long enough to process the command line options, call 67sched_setscheduler() and then switch back to the natural userid. This 68allows the program to call sched_setscheduler(), but prevents it from 69being able to overwrite any file (record mode), or to access any file 70(play mode) that it might otherwise be able to do, if the program 71continued to run as root. 72 73If running a program setuid root bothers you, or presents too much of a 74security risk, then comment out the SCHED_PRIORITY entry in the 75Makefile. 76 77As a further precaution, you will be required to do a 'make setuid_root' 78after the initial install, if you HAVE choosen to use the real time 79scheduling feature. By doing so you assume all of the risk associated 80with any possible security breach of running wavplay as a setuid root 81program. 82 83======================================= 84THE PAUSE BUTTON SEEMS TO LOSE SAMPLES: 85======================================= 86 87If you PLAY a wav file and then press PAUSE in xltwavplay, expect to 88lose a bunch of samples. The reason is fairly simple: serveral KB worth 89of samples are shoved into the /dev/dsp buffers to keep it well fed, 90since if it gets starved you'll hear glitches in the sound. 91 92To stop almost immediately, much of that queued data is dumped. So when 93you resume with PLAY, you'll often notice that some sound was lost. 94 95========================= 96YOU WANT TO REPORT A BUG: 97========================= 98 99Please give me something to work with when you submit the problem. A 100number of people tell me "its broken" and expect me to read minds. I 101don't read minds -- just ask my wife ;-) 102 103If it doesn't compile, get the error message text and forward _THAT_ to 104me. If you're using X, the use the mouse to copy the text of the screen 105and paste that into the message for me. 106 107Runtime errors from xltwavplay can be had by starting it from an xterm 108session, since many messages go to stderr. 109 110For catching compile errors, try: 111 112 $ make 2>&1 | tee errors.out 113 114To force a remake, try: 115 116 $ make clobber all 2>&1 | tee errors.out 117 118This allows you to see the messages in real time, and capture the 119messages to file errors.out as well. Include the contents of errors.out 120in your message to me please. 121 122Make sure you have sound support compiled into your kernel. 123 124Also please describe something about your system: 125 126 LINUX Kernel Version? (sometimes important) 127 CPU type? 128 Amount of memory? 129 What sound card type? (sometimes important) 130 Video card (if you think it has a bearing) 131 132Please describe your C compiler tools: 133 134 GCC --version 135 uname -a (lists some system info like kernel release) 136 137These are at least good places to start when reporting a bug. 138 139Anyway, for now, send all correspondance to ve3wwg@home.com. You can 140also check the web page at members.home.net/ve3wwg If all else fails, 141look for an updated LSM file entry on a ftp site near you 142(sunsite.unc.edu being my favourite). 143 144Please distinguish between the programs wavplay and xltwavplay when 145reporting problems. Note also, if the problem is with only certain wav 146files, or wav files from a certain tool, then please remember that 147wavplay does not properly process all legal variations of wav files at 148this time. 149 150If wavplay won't play or record at all, then make sure you have the 151sound card installed correctly. Ask yourself, does this work from 152DOS/Windoze ok? If not, then perhaps that's a place to start. If that's 153ruled out, then make sure your kernel has sound driver support and its 154configured OK. Newer kernels may require you to LOAD the module to 155support the sound driver. Make sure your special device file is 156available and has permissions (usually its /dev/dsp). 157 158Send correspondance to: 159 160 Warren W. Gay VE3WWG 161 ve3wwg@home.com 162 http://members.home.net/ve3wwg 163 164End BUGS. 165